CN113942657B - Repair method for rear edge and tip rear edge of composite blade - Google Patents
Repair method for rear edge and tip rear edge of composite blade Download PDFInfo
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- CN113942657B CN113942657B CN202111177058.XA CN202111177058A CN113942657B CN 113942657 B CN113942657 B CN 113942657B CN 202111177058 A CN202111177058 A CN 202111177058A CN 113942657 B CN113942657 B CN 113942657B
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- Prior art keywords
- rear edge
- blade
- damaged area
- repairing
- area
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64F—GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
- B64F5/00—Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
- B64F5/40—Maintaining or repairing aircraft
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
- B64C27/473—Constructional features
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C27/00—Rotorcraft; Rotors peculiar thereto
- B64C27/32—Rotors
- B64C27/46—Blades
- B64C27/473—Constructional features
- B64C2027/4733—Rotor blades substantially made from particular materials
- B64C2027/4736—Rotor blades substantially made from particular materials from composite materials
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
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- Engineering & Computer Science (AREA)
- Aviation & Aerospace Engineering (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Transportation (AREA)
- Adhesives Or Adhesive Processes (AREA)
Abstract
The application belongs to the field of rotor blade repair, and discloses a method for repairing a rear edge of a composite material blade and a rear edge of a blade tip by a bump, which comprises the following steps: and (3) a step of: judging the damage type as a bump at the rear edge of the blade or the rear edge of the blade tip; and II: judging whether the damaged area is polished or filled, if polished, entering three, and if filled, entering four to seven; thirdly,: polishing and paint supplementing the damaged areas of the blades; fourth, the method comprises the following steps: isolating a repair area by using an adhesive tape, and performing paint removal and copper mesh removal on the repair area, and cleaning; fifth step: filling filler in the damaged area, and maintaining the shape of the damaged area by using a maintenance tool for primary curing; sixth,: polishing the glue tumor until the shape of the blade in the filling area is consistent with the theoretical shape after the first curing is completed; seventh,: paving glass cloth and a copper net on the surface of the filling area, and carrying out secondary vacuum curing after the paving is finished; polishing, cleaning and paint repairing after the second curing is finished.
Description
Technical Field
The application belongs to the field of rotor blade repair, and in particular relates to a method for repairing a rear edge of a composite material blade and a rear edge of a blade tip by a gouging method.
Background
Composite blades have been increasingly used by helicopters because of the relatively high specific strength and stiffness and good fatigue resistance of the composite. The composite material blade inevitably damages in the use process, particularly the rear edge of the blade and the rear edge of the blade tip, and the blade is frequently knocked in the carrying, mounting and dismounting processes due to weak structure. The damage is repairable, and reasonable repair methods are needed to repair the blade in order to save cost and ensure the flight safety of the aircraft.
The existing repair method for the damaged skin of the composite material mainly adopts gradient lap joint repair, but the repair method is complex in implementation process, and in the process of repairing the damaged skin region into a gradient shape, the intact skin is easy to scratch due to the fact that the skin is thinner and not easy to peel off between layers, and the method needs to remove the larger area of the skin. In addition, the gradient lap joint repair uses prepreg and adhesive film, medium-temperature curing (about 120 ℃) is needed, the external field does not have implementation conditions, and the curing temperature is close to the blade mould pressing curing temperature, so that the strength of a blade non-damaged area can be influenced to a certain extent.
Therefore, a simple repair mode is needed, the operation is simple, the curing temperature is low, the outside field repair can be realized, and the use safety in flying can be ensured.
Disclosure of Invention
The application provides a repair method for the damage of the rear edge of a composite material blade and the rear edge of a blade tip, which adopts low-temperature curing, is simple to operate, can not bring secondary damage to the blade in the repair process, can ensure the safety of flying use, provides a reliable and simple external field repair means for the damage of the helicopter blade, prolongs the service life of the blade, and reduces the use and maintenance cost of the helicopter.
A repair method for the rear edge and the rear edge of a blade tip of a composite blade comprises the following steps: step one: judging the damage type as a bump at the rear edge of the blade or the rear edge of the blade tip;
step two: polishing the damaged area until no layering exists, judging whether the damaged area is polished or filled, if polished, entering a third step, and if filled, entering fourth to seventh steps;
step three: polishing the damaged area of the rear edge of the blade to be smooth and paint-repairing, polishing the damaged area of the blade tip to be arc-shaped and paint-repairing;
step four: isolating a repair area by using an adhesive tape, and performing paint removal and copper mesh removal on the repair area, and cleaning;
step five: filling filler in the damaged area, and maintaining the shape of the damaged area by using a maintenance tool for primary curing;
step six: polishing the glue tumor until the shape of the blade in the filling area is consistent with the theoretical shape after the first curing is completed;
step seven: paving glass cloth and a copper net on the surface of the filling area, and carrying out secondary vacuum curing after the paving is finished; polishing, cleaning and paint repairing after the second curing is finished.
Further, in the second step, for the damage of the rear edge of the blade, polishing and repairing are carried out when the spanwise length X of the damaged area is less than or equal to 20mm and the chordwise length Y is less than or equal to 4 mm;
filling and repairing when X is more than or equal to 10mm and less than or equal to 25mm and Y is more than or equal to 4 and less than or equal to 8mm in the damaged area;
for the damage of the rear edge of the blade tip, when the maximum radius R of a damaged area is less than or equal to 10mm, polishing and repairing are carried out; and when the maximum radius R of the damaged area is more than 10mm, the spanwise length X is less than or equal to 30mm, and the chordwise length Y is less than or equal to 15mm, filling and repairing are carried out.
Further, in the fifth step, for the rear edge of the blade to be knocked, the damaged area is filled with glue EA9309;
for the tip trailing edge gouges, the damaged area is filled with a mixture of glue EA9309 and sheared and dried glass cloth.
In the fifth step, for the blade trailing edge gouging and the blade tip trailing edge gouging, a pair of aluminum plates with the thickness of 1.5mm are fixed on two sides of a damaged area to be used as dimension tools, and the aluminum plates are clamped by using bow clamps;
for the damage of the rear edge of the blade tip, the side surface of the metal plate is wrapped with an adhesive tape as a maintenance tool to prevent the filler from sliding off.
Further, in the fifth step, the first curing condition is: and (3) curing for 5-7 days at room temperature or curing for 1h at 82+/-5 ℃ by a hot patching instrument after 24h at room temperature.
Further, in the step seven, for the bump at the rear edge of the blade, two layers of glass cloth are laid around the rear edge of the blade in a U-shaped manner;
for the gouging of the rear edge of the blade tip, U-shaped laying of inner-layer glass cloth around the surface of the blade tip, U-shaped laying of outer-layer glass cloth around the rear edge of the blade tip, and copper mesh laying on the outer surface of the outer-layer glass cloth, wherein U-shaped laying of the copper mesh is not adopted;
further, the second vacuum curing condition is that the room temperature curing is carried out for 5 to 7 days or the curing is carried out for 1.5 hours at 82+/-5 ℃ under the vacuum bag pressure, and the vacuum pressure is 0.06 to 0.1MPa.
Further, the distance L between the outer layer glass cloth and the boundary of the copper removal net is 3mm.
Advantageous effects
The repair method for the damage to the rear edge of the composite material blade and the rear edge of the blade tip has the advantages of clear repair route, simple process, no secondary damage to the blade, provision of a reliable repair means for the damage of the helicopter blade, prolonged service life of the blade, reduced use and maintenance cost of the helicopter, and the method has the following technical effects:
the application has clear repair route, simple process and strong operation feasibility;
the repairing method does not need to peel the skin, is simple to operate, and reduces accidental damage to the blade;
the repairing method has low curing temperature, and the curing temperature can not cause secondary damage to the blade;
the rear edge and the blade tip of the composite material blade are weak in structure and easy to collide and damage in the use field, and the repairing method provided by the application provides a reliable outfield repairing means, so that the service life of the blade is prolonged, and the use and maintenance cost of the helicopter is reduced;
the repairing method of the application is applied to the rotor blade of the helicopter for many times in China, and has better use effect through experiments and test flight verification.
Drawings
FIG. 1 (a) is a schematic view of a blade trailing edge gouging area according to the present application, and FIG. 1 (b) is a schematic view of a blade tip trailing edge gouging area according to the present application;
FIG. 2 (a) is a schematic view of a blade trailing edge gouging repair area and a copper mesh boundary removal according to the present application, and FIG. 2 (b) is a schematic view of a blade tip trailing edge gouging repair area and a copper mesh boundary removal according to the present application;
FIG. 3 is a schematic view of the blade tip trailing edge gouging and grinding repair scope of the present application;
FIG. 4 (a) is a schematic view of the blade trailing edge gouging filler repair of the present application, and FIG. 4 (b) is a schematic view of the blade tip trailing edge gouging filler repair of the present application;
fig. 5 (a) is a schematic view of the blade trailing edge gouging and spreading according to the present application, and fig. 5 (b) is a schematic view of the blade tip trailing edge gouging and spreading according to the present application;
fig. 6 (a) is a detailed view of a blade trailing edge gouging section according to the present application, and fig. 6 (b) is a detailed view of a blade tip trailing edge gouging section according to the present application.
Wherein, 1-the damaged area; 2-repair area boundaries; 3-adhesive tape; 4-removing the boundary of the copper net; 5-aluminum plate; 6-a bow clip; 7-inner layer glass cloth; 9-outer layer glass cloth; 10-copper mesh;
wherein X is the length of the spanwise injury; y is the chord damage length; l is the distance between the boundary of the copper net and the cut-off position of the outer layer glass cloth.
Detailed Description
The application is further illustrated by the following embodiments:
1) Referring to fig. 1,1 is a damaged area, and judging the damage type of the composite material blade as blade trailing edge gouging (a) or blade tip trailing edge gouging (b);
2) Referring to FIG. 2, for the damage of the rear edge of the blade, polishing the damaged area by a semicircular file until layering does not exist, when the spanwise length X of the damaged area is less than or equal to 20mm and the chordwise length Y of the damaged area is less than or equal to 4mm, polishing the damaged area smoothly and carrying out paint repair, and when the X of the damaged area is more than or equal to 10mm and less than or equal to 25mm and the Y of the damaged area is more than or equal to 4mm and less than or equal to 8mm, filling and repairing are carried out;
referring to fig. 2 and 3, for the gouging of the rear edge of the blade tip, polishing a damaged area by a flat file until layering does not exist, and polishing, repairing and paint supplementing when the maximum radius R of the damaged area is less than or equal to 10 mm; filling and repairing when the maximum radius R of the damaged area is more than 10mm, the spanwise length X is less than or equal to 30mm and the chordwise length Y is less than or equal to 15 mm;
3) Referring to fig. 2,2 is a repair area boundary, and for blade trailing edge gouging, the spanwise direction (x+86) mm and the chordwise direction (y+43) mm; for the damage of the rear edge of the blade tip, the spanwise direction is (X+43) mm, the chordwise direction is (Y+43) mm, the repairing area is isolated by using the adhesive tape 3, and the repairing area is paint-removed by using 80-mesh sand paper;
4) Referring to fig. 2, a glass scraper is used to remove copper mesh (if the structure has copper mesh) within boundary 4, boundary 2 being 5mm from boundary 4;
5) Cleaning the repair area by using acetone, and airing for 90min;
6) Preparing a filling material, and filling adhesive EA9309 in a damaged area for the damage of the rear edge of the blade; for the damage of the rear edge of the blade tip, the structure of the damage area is weak, and the rigidity and strength of the damage area can be increased by filling the mixture of glue EA9309 and sheared and dried glass cloth in the damage area;
7) Referring to fig. 4, for blade trailing edge gouges and blade tip trailing edge gouges, a pair of aluminum plates 5 (tape attached to one side of the blade for protection) with a thickness of 1.5mm are used for fixing at two sides of a damaged area to serve as dimension tools, and a bow clamp 6 is used for clamping the aluminum plates;
for the gouging of the rear edge of the blade tip, the side surface of the metal plate is wrapped with the adhesive tape 7 as a maintenance tool to prevent the filler from sliding off;
8) For the rear edge gouging of the blade, using a spatula to fill the gap with adhesive EA9309; for the gouging of the rear edge of the blade tip, filling the mixture of the sheared glass cloth and the adhesive EA9309 into the cavity by using a spatula;
9) The first curing condition can be that room temperature curing is adopted for 5-7 days, or after room temperature curing is carried out for 24 hours, the arch clamp is removed, and a hot patching instrument is used for curing for 1 hour at 82+/-5 ℃;
10 Removing the curing equipment when the temperature is reduced to below 40 ℃, polishing and shaping by using 80-mesh sand paper, wherein the shape of the blade in the filling area is consistent with the theoretical shape;
11 Cleaning the polished area by using acetone, and airing for 90min;
12 Referring to fig. 5, the boundary of the inner layer glass cloth 8 is (x+15) mm, (y+15) mm, the boundary of the outer layer glass cloth 9 is (x+30) mm, (y+30) mm, and the boundary of the copper mesh 10 (if the structure has a copper mesh) is consistent with the outer layer glass cloth 9;
13 Preparing an adhesive EA9309, a dry glass cloth and a copper mesh (if the structure is provided with the copper mesh), dipping the dry glass cloth, and ensuring the glue content to be more than 50%;
13 Referring to fig. 5 and 6, for the damage of the rear edge of the blade, two layers of glass cloth are laid around the rear edge of the blade in a U-shaped manner; for the damage of the rear edge of the blade tip, the inner glass cloth 8 is laid around the U-shaped end face of the blade tip, and the outer glass cloth 9 is laid around the U-shaped end face of the blade tip, so that better tightness of the edge can be ensured. The copper net 10 is laid outside the outer layer glass cloth, and the copper net is not laid in a U shape;
the distance between the outer layer glass cloth 9 and the removed copper mesh boundary 4 is 3mm, so that the glass cloth is prevented from extending to the original blade copper mesh and affecting the bonding quality;
14 Covering the repair area with demolding cloth, and making a vacuum bag for vacuumizing and curing;
15 Secondary vacuum curing conditions): curing for 5-7 days or for 1.5 hours at 82+/-5 ℃ under the vacuum bag pressure at room temperature and the vacuum pressure of 0.06-0.1 MPa;
16 Grinding the redundant glue tumor by using 80-mesh sand paper, and cleaning process auxiliary materials;
17 Knocking and size checking are carried out on the repairing area to ensure that layering does not exist, the thickness of the rear edge is increased by not more than 1mm, if the thickness exceeds the thickness, polishing and repairing are carried out, and the influence of the repairing on the pneumatic appearance of the blade is limited;
18 And (3) paint repair the repair area.
In summary, the repair method for the damage to the rear edge of the composite material blade and the rear edge of the blade tip has the advantages of clear repair route, simple process, outfield operation and no secondary damage to the blade, provides a reliable outfield repair means for the damage of the helicopter blade, prolongs the service life of the blade, and reduces the use and maintenance cost of the helicopter.
The foregoing is merely a detailed description of the application, which is not a matter of routine skill in the art. However, the scope of the present application is not limited thereto, and any changes or substitutions that can be easily contemplated by those skilled in the art within the scope of the present application should be included in the scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.
Claims (4)
1. A repair method for the rear edge and the rear edge of a blade tip of a composite blade is characterized by comprising the following steps: the method comprises the following steps: step one: judging the damage type as a bump at the rear edge of the blade or the rear edge of the blade tip;
step two: polishing the damaged area until no layering exists, judging whether the damaged area is polished or filled, if polished, entering a third step, and if filled, entering fourth to seventh steps;
step three: polishing the damaged area of the rear edge of the blade to be smooth and paint-repairing, polishing the damaged area of the blade tip to be arc-shaped and paint-repairing;
step four: isolating a repair area by using an adhesive tape, and performing paint removal and copper mesh removal on the repair area, and cleaning;
step five: filling a filler in a damaged area, and filling glue EA9309 in the damaged area for the damage of the rear edge of the blade; for the gouging of the rear edge of the blade tip, filling a mixture of glue EA9309 and sheared and dried glass cloth in a damaged area, and maintaining the shape of the damaged area by using a maintenance type tool for primary curing; solidifying for 5-7 days at room temperature;
step six: polishing the glue tumor until the shape of the blade in the filling area is consistent with the theoretical shape after the first curing is completed;
step seven: for the gouging of the rear edge of the blade, two layers of glass cloth are laid around the U-shaped rear edge of the blade; for the damage of the rear edge of the blade tip, the inner layer glass cloth is laid around the U-shaped part of the end face of the blade tip, the outer layer glass cloth is laid around the U-shaped part of the rear edge of the blade tip, the copper mesh is laid on the outer surface of the outer layer glass cloth, the copper mesh is not laid in a U-shaped way, the boundary of the inner layer glass cloth is (X+15) mm, (Y+15) mm, the boundary of the outer layer glass cloth is (X+30) mm, (Y+30) mm, the boundary of the copper mesh is consistent with the outer layer glass cloth 9, X and Y are the spanwise length and chord width of a damaged area, the second vacuum curing is carried out after the laying is completed, the vacuum bag is pressed down for room temperature curing for 5-7 days or 82+/-5 ℃ for curing for 1.5 hours, and the vacuum pressure is 0.06-0.1 MPa; polishing, cleaning and paint repairing after the second curing is finished.
2. The method for repairing the damage to the rear edge and the tip rear edge of the composite material blade according to claim 1, wherein in the second step, for the damage to the rear edge of the blade, polishing and repairing are performed when the spanwise length X of a damaged area is less than or equal to 20mm and the chordwise length Y is less than or equal to 4 mm;
filling and repairing when X is more than or equal to 10mm and less than or equal to 25mm and Y is more than or equal to 4 and less than or equal to 8mm in the damaged area;
for the damage of the rear edge of the blade tip, when the maximum radius R of a damaged area is less than or equal to 10mm, polishing and repairing are carried out; and when the maximum radius R of the damaged area is more than 10mm, the spanwise length X is less than or equal to 30mm, and the chordwise length Y is less than or equal to 15mm, filling and repairing are carried out.
3. The method for repairing the rear edge and the tip rear edge of the composite material blade according to claim 2, wherein in the fifth step, for the rear edge and the tip rear edge of the blade, a pair of aluminum plates with the thickness of 1.5mm are used for fixing the two sides of a damaged area as dimensional tools, and an arch clamp is used for clamping the aluminum plates;
for the damage of the rear edge of the blade tip, the side surface of the metal plate is wrapped with an adhesive tape as a maintenance tool to prevent the filler from sliding off.
4. The method for repairing the knocks and the damages of the rear edge of the blade and the rear edge of the blade tip made of the composite material according to claim 1, wherein the distance L between the outer glass cloth and the boundary of the copper removal net is 3mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111177058.XA CN113942657B (en) | 2021-10-09 | 2021-10-09 | Repair method for rear edge and tip rear edge of composite blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111177058.XA CN113942657B (en) | 2021-10-09 | 2021-10-09 | Repair method for rear edge and tip rear edge of composite blade |
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| Publication Number | Publication Date |
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| CN113942657A CN113942657A (en) | 2022-01-18 |
| CN113942657B true CN113942657B (en) | 2023-09-08 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202111177058.XA Active CN113942657B (en) | 2021-10-09 | 2021-10-09 | Repair method for rear edge and tip rear edge of composite blade |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104632815A (en) * | 2015-01-26 | 2015-05-20 | 哈尔滨飞机工业集团有限责任公司 | Helicopter blade rear edge reinforcing plate glue failure repair method |
| CN105730715A (en) * | 2016-03-23 | 2016-07-06 | 哈尔滨飞机工业集团有限责任公司 | Repairing method for local damage of composite flap |
| CN108622436A (en) * | 2018-06-22 | 2018-10-09 | 江西昌河航空工业有限公司 | A kind of repair method after composite material blade damage |
| CN110561796A (en) * | 2019-09-19 | 2019-12-13 | 哈尔滨哈飞航空工业有限责任公司 | Reinforcing and repairing method for damaged composite material blade skin |
| FR3082232A1 (en) * | 2018-06-12 | 2019-12-13 | Safran Aircraft Engines | HOLDING SYSTEM FOR DISASSEMBLING A BLADE WHEEL |
-
2021
- 2021-10-09 CN CN202111177058.XA patent/CN113942657B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104632815A (en) * | 2015-01-26 | 2015-05-20 | 哈尔滨飞机工业集团有限责任公司 | Helicopter blade rear edge reinforcing plate glue failure repair method |
| CN105730715A (en) * | 2016-03-23 | 2016-07-06 | 哈尔滨飞机工业集团有限责任公司 | Repairing method for local damage of composite flap |
| FR3082232A1 (en) * | 2018-06-12 | 2019-12-13 | Safran Aircraft Engines | HOLDING SYSTEM FOR DISASSEMBLING A BLADE WHEEL |
| CN108622436A (en) * | 2018-06-22 | 2018-10-09 | 江西昌河航空工业有限公司 | A kind of repair method after composite material blade damage |
| CN110561796A (en) * | 2019-09-19 | 2019-12-13 | 哈尔滨哈飞航空工业有限责任公司 | Reinforcing and repairing method for damaged composite material blade skin |
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| CN113942657A (en) | 2022-01-18 |
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